JP2005242310A - Liquid crystal display device and method of fabricating same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device whose defects are improved by providing column spacers at different parts of a step of a TFT substrate, and a fabricating method therefor. <P>SOLUTION: The liquid crystal display includes a first substrate having first and second regions thereon, the first region having a step coverage higher than a step coverage of the second region, a second substrate bonded to the first substrate, the second substrate having a first column spacer corresponding to the first region of the first substrate and a second column spacer corresponding to the second region of the first substrate, and a liquid crystal layer formed between the first and second substrates. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device in which defects are improved by providing column spacers at different portions of a TFT substrate and a method for manufacturing the same.

With the development of the information society, demands for display devices are also demanded in various forms. Recently, LCD (Liquid Crystal Display Device), PDP (Plasma Display Panel), ELD (Electro Luminescent Display), VF Various flat panel display devices such as (Vacuum Fluorescent Display) have been studied, and some of them have already been utilized in various types of display devices.

Among them, at present, LCDs are used most frequently in place of CRT (Cathode Ray Tube) in applications of mobile image display devices because of their excellent image quality, light weight and thinness, and low power consumption. In addition to mobile applications such as notebook computer monitors, various developments have been made in televisions and computer monitors that receive and display broadcast signals.

In order to use such a liquid crystal display device in various places as a general screen display device, while maintaining the features of light weight, thinness, and low power consumption, it has high quality with high definition and high brightness on a large screen. It is no exaggeration to say that it depends on how much the image can be realized.

Hereinafter, a conventional liquid crystal display device and a spacer for maintaining a cell gap of the liquid crystal display device will be described with reference to the accompanying drawings.

FIG. 1 is an enlarged perspective view showing a general liquid crystal display device. As shown in FIG. 1, the liquid crystal display device is injected between the first substrate 1 and the second substrate 2 bonded together with a certain space, and the first substrate 1 and the second substrate 2. And the liquid crystal layer 3.

More specifically, in order to define the pixel region P, the first substrate 1 includes a plurality of gate lines 4 in one direction at a predetermined interval and a direction perpendicular to the gate lines 4. A plurality of data lines 5 are arranged at regular intervals. A pixel electrode 6 is formed in each pixel region P, and a thin film transistor T is formed at a portion where each gate line 4 and each data line 5 intersect, and the thin film transistor receives the data according to the signal of the gate line. A line data signal is applied to each pixel electrode.

A black matrix layer 7 is formed on the second substrate 2 to block light except for the pixel region P, and R for expressing a hue in a portion corresponding to each pixel region. G and B color filter layers 8 are formed, and a common electrode 9 for forming an image is formed on the color filter layer 8.

In the liquid crystal display device as described above, the liquid crystal layer 3 formed between the first substrate 1 and the second substrate 2 is aligned by the electric field between the pixel electrode 6 and the common electrode 9, and the liquid crystal layer An image can be expressed by adjusting the amount of light transmitted through the liquid crystal layer 3 according to the degree of orientation of 3.

Such a liquid crystal display device is called a TN mode liquid crystal display device, and the TN mode liquid crystal display device has a disadvantage that the viewing angle is narrow. In order to overcome such a disadvantage of the TN mode, an IPS (in. -plane switching) mode liquid crystal display device was developed.

In the IPS mode liquid crystal display device, a pixel electrode and a common electrode are formed in parallel to each other at a certain distance in a pixel region of a first substrate, and an electric field is parallel to the substrate between the pixel electrode and the common electrode. The liquid crystal layer is aligned by this electric field.

Hereinafter, a method of manufacturing a conventional IPS mode liquid crystal display device will be described.

A general method for manufacturing a liquid crystal display device can be classified into a liquid crystal injection method manufacturing method by a method of forming a liquid crystal layer between a first substrate and a second substrate, and a liquid crystal dropping method manufacturing method. First, a method for manufacturing a liquid crystal injection type liquid crystal display device is as follows.

FIG. 2 is a flowchart showing a method of manufacturing a general liquid crystal injection type liquid crystal display device. A liquid crystal display device is roughly classified into an array process, a cell process, a module process, and the like. As described above, in the array process, the gate line and the data line formed in the direction perpendicular to the TFT substrate, the common line formed in parallel to the gate line, and the gate line and the data line intersect. A thin film transistor formed in a portion, a common electrode extending from the common line to a pixel region, a drain electrode of the thin film transistor, and a pixel formed in parallel with the common electrode between the common electrodes This is a step of forming a TFT array including electrodes and forming a color filter array including a black matrix layer, a color filter layer, an overcoat layer, and the like on a color filter substrate.

At this time, the array process does not form one liquid crystal panel on one substrate, but designs a plurality of liquid crystal panels on one large glass substrate, and a TFT array and a color in each liquid crystal panel region. A filter array is formed. As described above, the TFT substrate on which the TFT array is formed and the color filter substrate on which the color filter array is formed move to the cell process line.

Next, an alignment material is applied on the TFT substrate and the color filter substrate, and an alignment process (rubbing process) (S10) is performed to make liquid crystal molecules have a uniform direction. Here, the alignment process S10 is performed in the order of cleaning before alignment film application, alignment film printing, alignment film plasticity, alignment film inspection, and rubbing process.

Next, the TFT substrate and the color filter substrate are respectively cleaned (S20). Then, a ball spacer for maintaining a constant cell gap is sprayed on the TFT substrate or the color filter substrate (30), and a seal pattern for bonding both substrates to the outer portion of each liquid crystal panel region is formed. (S40). At this time, the seal pattern is formed to have a liquid crystal inlet pattern for injecting liquid crystal.

Here, the ball spacer is formed of a plastic ball or elastic plastic fine particles. The TFT substrate and the color filter substrate are faced to each other so that the seal pattern is located between them, and the two substrates are bonded together, and the seal pattern is cured (S50). Thereafter, the bonded and cured TFT substrate and color filter substrate are cut for each unit liquid crystal panel region and processed (S60) to manufacture a unit liquid crystal panel of a certain size.

Thereafter, liquid crystal is injected through the liquid crystal injection port of each unit liquid crystal panel, and after the injection is completed, the liquid crystal injection port is sealed (S70) to form a liquid crystal layer. Then, the appearance and electrical defect inspection (S80) of each unit liquid crystal panel is advanced to manufacture a liquid crystal display device.

Here, the liquid crystal injection process will be briefly described. First, a container in which liquid crystal material to be injected is placed and a liquid crystal panel to inject liquid crystal are positioned inside the chamber, and the pressure in the chamber is maintained in a vacuum state so that the liquid crystal material is attached inside or inside the container. Moisture is removed and bubbles are removed, and at the same time, the internal space of the liquid crystal panel is evacuated.

Then, after the liquid crystal inlet of the liquid crystal panel is immersed or brought into contact with a container containing a liquid crystal substance in a desired vacuum state, the pressure inside the chamber is changed from a vacuum state to an atmospheric pressure state, The liquid crystal material is injected into the liquid crystal panel through the liquid crystal injection port according to the difference between the pressure in the chamber and the pressure in the chamber.

However, the manufacturing method of such a liquid crystal injection type liquid crystal display device has the following problems.

First, after cutting the unit panel, maintaining a vacuum between the two substrates and immersing the liquid crystal injection port in the liquid crystal solution to inject the liquid crystal requires a lot of time for liquid crystal injection, and productivity Decreases.

Second, when manufacturing a large-area liquid crystal display device, if the liquid crystal is injected by the liquid crystal injection method, the liquid crystal is not completely injected into the panel, which causes a defect.

Third, since the process is complicated and requires a lot of time as described above, a plurality of liquid crystal injection equipment is required and a lot of space is required. Therefore, in order to overcome such problems of the liquid crystal injection method, a method of manufacturing a liquid crystal dropping type liquid crystal display device in which liquid crystal is dropped on one of the two substrates and then bonded to each other has been developed. .

FIG. 3 is a flowchart showing a manufacturing method of the liquid crystal dropping type liquid crystal display device. In other words, the liquid crystal dropping type liquid crystal display device manufacturing method is a method in which an appropriate amount of liquid crystal is dropped onto one of the two substrates before the two substrates are bonded together, and then the two substrates are bonded together. Therefore, when using a ball spacer to maintain the cell gap as in the liquid crystal injection method, the ball spacer moves in the liquid crystal diffusion direction when the dropped liquid crystal spreads, and the spacer is shifted to one side. It becomes impossible to maintain the cell gap. Therefore, in the liquid crystal dropping method, a ball spacer is not used, but a fixed spacer (column spacer or patterned spacer) in which the spacer is fixed to the substrate must be used.

That is, as shown in FIG. 3, in the array process, a black matrix layer, a color filter layer, and a common electrode are formed on a color filter substrate, a photosensitive resin is formed on the common electrode, and selectively removed. A column spacer is formed on the black matrix layer. Of course, the column spacer can be formed by a photo process or an inkjet process. Then, an alignment film is applied to the entire surface of the TFT substrate including the column spacer and the color filter substrate, and the alignment film is rubbed.

As described above, after the alignment process is completed and the TFT substrate and the color filter substrate are respectively cleaned (S101), the liquid crystal is dropped onto a certain region on one of the TFT substrate and the color filter substrate (S102). Then, a seal pattern is formed on the outer portion of each liquid crystal panel region of the other substrate using a dispensing device (S103). At this time, liquid crystal may be dropped on one of the two substrates and a seal pattern may be formed.

Then, the substrate on which the liquid crystal is not dropped is reversed (turned over so as to face each other) (S104), the TFT substrate and the color filter substrate are pressed and bonded together, and the seal pattern is cured (S105).

Next, the bonded substrate described above is cut and processed for each unit liquid crystal panel (S106). Then, by proceeding with the appearance and electrical defect inspection (S107) of the processed unit liquid crystal panel, a liquid crystal display element is manufactured.

In such a liquid crystal dropping method, a column spacer is formed on a color filter substrate, a liquid crystal is dropped on the TFT substrate, and the two substrates are bonded to form a panel. At this time, the column spacer is fixed to the color filter substrate and is in contact with the TFT substrate. The portion in contact with the TFT substrate is formed with a certain height on the color filter substrate corresponding to either the single wiring of the gate line or the data line.

However, in the following, the column spacer of the liquid crystal display element formed by such a liquid crystal dropping method and the problems caused on the panel by the column spacer at the time of bonding will be considered.

First, in the case of a liquid crystal display device formed by a conventional liquid crystal dropping method, the column spacer is formed on the color filter substrate corresponding to the gate line or the data line. In this case, the column spacers are formed at the same height in a single wiring region (gate line or data line) having no step.

In the case of the conventional liquid crystal display device, when the column spacer is bonded to the TFT substrate corresponding to the same height, the column spacer has a low supporting force to support the two substrates, thereby causing a gravity defect. Generally, when a liquid crystal display device is left in a high temperature state, a phenomenon that the liquid crystal swells due to the property of expanding at a high temperature occurs. In particular, when the panel is erected, such a phenomenon becomes more serious on the corner side of the panel close to the ground. This phenomenon is called poor gravity.

FIG. 4A is a structural cross-sectional view showing a color filter substrate on which column spacers are formed. FIG. 4B is a structural cross-sectional view showing the shape when the TFT substrate and the color filter substrate are bonded together.

As shown in FIG. 4A, a plurality of column spacers 20 are formed on the black matrix layer (not shown) region of the color filter substrate 2 at a predetermined interval. In this case, each of the column spacers 20 is formed at a height of h. As described above, when the color filter substrate 2 on which the column spacer 20 is formed is bonded to the TFT substrate 1 as shown in FIG. 4B, the column spacer 20 has a height h representing the cell gap by the pressure applied. Shrink with ´.

As shown in FIGS. 4A and 4B, the column spacer 20 in the panel 10 contracts to the height of the cell gap h ′ after bonding, and thus the actual column spacer formation height h and The column spacer 20 has a supporting force for the TFT substrate 1 and the color filter substrate 2 as compared with the expansion force of the liquid crystal at a high temperature by a thickness (h−h ′) corresponding to the difference from the cell gap h ′. Here, the thickness (h−h ′) corresponding to the difference between the actual column spacer formation height h and the cell gap h ′ means a gravity margin.

In the case of a conventional liquid crystal display device, a column spacer is formed in a single wiring region corresponding to the same step, and the thickness (hh ′) is limited to about 0.1 μm to 0.15 μm. In addition, the weight margin was very low, and due to the difference in height between the column spacers formed by patterning, nonuniformity of the gravity defect in each region was observed in the entire panel.

Second, since the column spacer is fixed to one substrate and the surface in contact with the other substrate is not spherical, the area contacting the substrate is larger than that of the ball spacer, and the frictional force with the substrate is large. Therefore, when the screen of the liquid crystal display device on which the column spacer is formed is rubbed, a long-time stain occurs.

5A and 5B are a plan view and a cross-sectional view showing a state where a touch spot is generated. As shown in FIG. 5A, when the liquid crystal panel 10 is shifted while being touched with a finger in a predetermined direction, as shown in FIG. 5B, the upper substrate 2 of the liquid crystal panel 10 has a predetermined direction in the direction in which the finger is displaced. Shift at intervals. At this time, since the columnar column spacer 20 touches the upper and lower substrates 1 and 2 and the contact area increases, the frictional force generated between the column spacer 20 and the counter substrate (lower substrate 1) is large. Therefore, since the liquid crystal 3 between the column spacers 20 is not easily returned to the original state and remains as it is, a stain that looks opaque is continuously observed.

Further, when the finger is touched in a predetermined direction, as shown in FIG. 5B, the liquid crystal 3 gathers at the last contact portion, and the portion swells. In this case, the portion where the liquid crystal gathers and expands has a cell gap (h1) higher than the cell gap (h2) of the other portion defined by the height of the column spacer 20, and the alignment of the liquid crystal 3 is not uniform. Therefore, light leakage occurs.

In addition, since the liquid crystal is scattered at the part touched while the finger is displaced on the panel 10 surface, the liquid crystal does not remain in the part and a thin stain occurs in the black state. This is a factor that decreases the brightness.

Third, the ball spacer used in the liquid crystal injection method is scattered in a large amount and is spherical, and when a predetermined area of the panel is pressed, the ball spacer of the corresponding part slides sideways, Although the column spacer is selectively formed in the portion excluding the pixel area, the substrate is easily bent when the portion where the column spacer is not formed is pushed, and the cell gap of the pushed portion is also formed. A pressing failure, which is a phenomenon of breaking without being maintained, is also observed.

The present invention has been devised to solve the above-mentioned problems, and provides a liquid crystal display device in which column spacers are provided at different portions of a TFT substrate to improve defects and a method for manufacturing the same. There is that purpose.

In order to achieve the above object, a liquid crystal display device according to the present invention includes a first substrate having a first region having a relatively high step and a second region having a relatively low step, and the first substrate of the first substrate. The first substrate is provided in a portion corresponding to one region, the second substrate is provided in a portion corresponding to the second region, and the first substrate is bonded to the first substrate. And a liquid crystal layer formed between the two substrates.

The first column spacer and the second column spacer have the same height.

The first column spacer presses a corresponding surface on the first substrate to maintain a cell gap of the liquid crystal layer.

The height of the first column spacer contracts by a difference in height between the first region and the second region of the first substrate.

The first column spacer contracts to a thickness of 2000 mm to 6000 mm.

The second column spacer contacts the first substrate.

The second column spacer is separated from the first substrate at a predetermined interval.

The first height of the second column spacer decreases to a second height when pressure is applied to the second substrate.

A TFT array is formed on the first substrate, and a color filter array is formed on the second substrate.

The TFT array defines a pixel region on a first substrate, and a plurality of gate lines and data lines intersecting each other vertically, and a plurality of thin film transistors formed at intersections of the gate lines and data lines. And a plurality of common electrodes and pixel electrodes alternately formed in each pixel region.

The color filter array includes a black matrix layer formed on a second substrate corresponding to the metal wiring and thin film transistor of the TFT array, a color filter layer formed on the second substrate including the black matrix layer, And an overcoat layer formed on the color filter layer.

The first column spacer is formed corresponding to the source electrode of the thin film transistor.

The first column spacer is formed corresponding to the drain electrode of the thin film transistor.

The first column spacer is formed corresponding to an upper portion of the gate electrode of the thin film transistor.

The first column spacer is formed corresponding to a contact region between the thin film transistor and the pixel electrode.

An ITO film is further included on the entire back surface of the first substrate.

The plurality of column spacers are formed on the color filter array.

The first column spacer and the second column spacer are formed on the black matrix layer.

The TFT array defines a pixel region, and a plurality of gate lines and data lines that intersect perpendicularly to each other, a plurality of thin film transistors formed at intersections of the gate lines and the data lines, And a plurality of pixel electrodes formed in each pixel region.

The color filter array includes a black matrix layer formed corresponding to a metal wiring and a thin film transistor forming part of the TFT array, a color filter layer formed on a second substrate including the black matrix layer, and the color And a common electrode formed on the filter layer.

The first column spacer is formed corresponding to the source electrode of the thin film transistor.

The first column spacer is formed corresponding to the drain electrode of the thin film transistor.

The first column spacer is formed corresponding to an upper portion of the gate electrode of the thin film transistor.

The first column spacer is formed corresponding to a contact area between the one thin film transistor and the one pixel electrode.

The first column spacer and the second column spacer are formed corresponding to the black matrix layer forming portion.

The image forming apparatus further includes a plurality of alignment films formed on surfaces of the first substrate and the second substrate facing each other.

In order to achieve the above object, a liquid crystal display device according to the present invention is formed on a first substrate and a second substrate facing each other and on the first substrate to define a pixel region. A plurality of gate lines and data lines; a plurality of thin film transistors formed at intersections of the gate lines and the data lines; a plurality of pixel electrodes and a common electrode formed in each pixel region; A first column spacer formed on the second substrate corresponding to the one thin film transistor, and a first column spacer formed on the second substrate corresponding to the one gate line or the one data line. It comprises a two-column spacer and a liquid crystal layer formed between the first substrate and the second substrate.

The first thickness of the first column spacer decreases to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate.

The first column spacer and the second column spacer are formed at the same height.

In order to achieve the above object, a liquid crystal display device according to the present invention is formed on a first substrate and a second substrate facing each other and on the first substrate to define a pixel region. A plurality of gate lines and data lines; a plurality of thin film transistors formed at intersections of the gate lines and the data lines; a plurality of pixel electrodes formed in the pixel regions; A first column spacer formed on the second substrate corresponding to one thin film transistor, and a second column formed on the second substrate corresponding to the one gate line or the one data line. It includes a spacer and a liquid crystal layer formed between the first substrate and the second substrate.

A first thickness of the first column spacer decreases to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate.

The first column spacer and the second column spacer are formed at the same height.

In order to achieve the above object, a liquid crystal display device according to the present invention is formed on a first substrate and a second substrate facing each other and on the first substrate to define a pixel region. A plurality of gate lines and data lines; a plurality of thin film transistors formed at intersections of the gate lines and the data lines; a plurality of pixel electrodes and a common electrode formed in each pixel region; A first column spacer formed on the second substrate corresponding to an intersection of the gate line and the data line, and a gate line or a data line excluding the intersection of the gate line and the data line. And a second column spacer formed on the second substrate, and a liquid crystal layer formed between the first substrate and the second substrate.

The first thickness of the first column spacer decreases to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate.

The first column spacer and the second column spacer are formed at the same height.

In order to achieve the above object, a liquid crystal display device according to the present invention is formed on a first substrate and a second substrate facing each other and on the first substrate to define a pixel region. A plurality of gate lines and data lines; a plurality of thin film transistors formed at intersections of the gate lines and the data lines; a plurality of pixel electrodes formed in the pixel regions; A first column spacer formed on the second substrate corresponding to the intersection of the line and the data line, and a gate line or data line corresponding to the gate line or the data line excluding the intersection of the gate line and the data line. A second column spacer formed on the second substrate, and a liquid crystal layer formed between the first substrate and the second substrate.

The first thickness of the first column spacer decreases to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate.

The first column spacer and the second column spacer are formed at the same height.

In order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention includes a step of preparing a first substrate on which a TFT array is formed, and a color filter array is formed so as to face the first substrate. A first column spacer and a second column spacer are formed on the second substrate corresponding to the step of preparing the second substrate, the first region having a relatively high step, and the second region having a relatively low step. And a step of forming a liquid crystal layer between the first substrate and the second substrate, and a step of bonding the first substrate and the second substrate together.

The first column spacer is formed on a second substrate corresponding to a first region of the thin film transistor array of the first substrate, and the second column spacer is a gate line excluding the first region of the first substrate. Alternatively, it is formed corresponding to the data line area.

The first region of the first substrate corresponds to a thin film transistor region of the thin film transistor array.

A first region of the thin film transistor array formed on the first substrate corresponds to an intersection of the gate line and the data line.

The first column spacer and the second column spacer are formed at the same height.

The liquid crystal display device and the manufacturing method thereof according to the present invention have the following effects.

First, the column spacers can be formed with an appropriate density that does not cause a pressing failure, thereby preventing a pressing failure that breaks the cell gap of the panel. That is, a separate column spacer is further formed on one pixel in addition to the cell gap maintaining column spacer to solve pressing unevenness due to pressing failure.

Second, by forming column spacers at the same height corresponding to the portions having different steps on the TFT substrate, some column spacers touch the TFT substrate, and some column spacers Is pressed in contact with the TFT substrate by the pressure at the time of bonding, and the column spacer contracts by the height pressed in contact with the TFT substrate, so that the height can act as a gravity margin.

Third, the column spacer corresponding to the portion of the TFT substrate having a low step is actually not touched with the TFT substrate only at the time of bonding after the array is formed, or is separated or pushed within the range of 2000 mm. To be formed. That is, the pressing force between the column spacer and the counter substrate can be reduced to reduce the frictional force between the TFT substrate and the column spacer, thereby improving the touch unevenness generated when the panel is touched.

Fourth, according to the TFT design, a relatively high portion and a relatively low portion of the step are determined by the step of the TFT substrate, and the first column spacer and the second column spacer are respectively the same so as to correspond to the portion. The gravity defect is improved by using the characteristics of the design structure of the TFT substrate without changing the separate spacer formation process.

Fifth, the column spacers for maintaining the cell gap are formed so that a predetermined thickness or more is pushed to a high stepped portion, so that the column spacers are patterned when the column spacers formed on the color filter substrate are patterned. This step can sufficiently compensate for the non-uniformity of gravity failure that occurs in each panel area.

Hereinafter, a liquid crystal display device and a manufacturing method thereof according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 6 is a graph showing touch unevenness and poor gravity due to liquid crystal dripping amount and column spacer density change. In the manufacture of a large area liquid crystal display device, it is manufactured by a liquid crystal dropping method from the advantage of shortening the process time, and a column spacer is used as a support between the upper and lower substrates, but as shown in FIG. The density of the column spacer is a major factor that affects the degree of panel failure as well as the amount of liquid crystal dripped.

Defects that mainly occur in large-area liquid crystal display devices include poor gravity, uneven touch, and poor press. First, poor gravity refers to a phenomenon in which when the panel is erected, the liquid crystal is shifted to the side closer to the ground, and that part expands as the liquid crystal rises in temperature, causing the corners of the panel near the ground to swell in a hot state. .

Touch unevenness refers to a situation in which when a liquid crystal panel surface is touched in a predetermined direction with a hand or a pen, the portion touched by the hand or pen is not restored by frictional force, and the liquid crystal is scattered on the touched portion. At this time, the liquid crystal does not collect in the unrestored portion, and a light leakage defect appears in a black state. This is because a shift phenomenon occurs in a predetermined direction between the upper and lower substrates when touched, but it does not return to the original state because the frictional force between the substrates touching the column spacer is large.

When the column spacers are distributed at a low density between the upper and lower substrates, the cell gap collapses without being recovered when the portion where the column spacers are not formed is pushed by applying a predetermined force. State.

Defects as described above do not exist due to elements independent of each other, but occur with interrelationships. In particular, gravity failure and touch unevenness are in a trade-off relationship with the liquid crystal dripping amount, and the liquid crystal dripping amount should not be adjusted in a direction to improve only a certain defect. The liquid crystal dripping amount should be determined so that

Thus, when the liquid crystal dropping amount is determined to be an appropriate amount, it is the density of the column spacer that determines the panel failure. That is, when the density of the column spacer is relatively low, both gravity failure and touch unevenness can be improved. In addition, the resistance to external pressure is weak, and a pressing failure that cannot recover a broken cell gap is likely to occur. Therefore, distributing an appropriate level of column spacers between the upper and lower substrates is an important point for improving the pressing failure.

The liquid crystal display device and the manufacturing method thereof according to the present invention is characterized in that a column spacer is formed on a color filter substrate in accordance with each portion having different steps of a TFT substrate having steps, and the cell gap is reduced. In addition to maintaining, a separate column spacer is further formed in the pixel to prevent a pressing failure that causes the cell gap to collapse due to external pressure.

Further, the separate column spacer formed outside the cell gap is formed so as to be in contact with, separated from, or pressed against the counter substrate within a predetermined range. Minimize the contact force between and improve touch unevenness.

In addition, in the case of poor gravity caused by the property that the liquid crystal expands at a high temperature, there should be a gravity margin for the thickness corresponding to the difference between the thickness at the time of forming the column spacer and the thickness at the time of bonding. In consideration of the above, when one of the column spacers is pasted, it is formed so as to be pushed further by a predetermined thickness corresponding to the high stepped portion so as to have a gravity margin of the predetermined thickness. . In addition, the panel generated by the difference in the height of the column spacers formed by patterning has sufficient gravity margin for each pixel as much as the counter substrate is further pushed by a certain thickness by one column spacer. It is possible to improve the non-uniformity of gravity failure by area.

7A to 7C are structural cross-sectional views schematically showing the liquid crystal display device of the present invention. 7A, the liquid crystal display device of the present invention is formed on a first substrate 100 having regions with different steps, a second substrate 200 facing the first substrate 100, and a high step portion 80 of the first substrate 100. A first column spacer 301 and a second column spacer 302 formed in a low step portion 85 of the first substrate 100.

Here, the first column spacer 301 and the second column spacer 302 are formed on the black matrix layer 201 and have the same height.

The first substrate 100 is a lower substrate on which a TFT array is formed, and a gate line or a data line is an intersection of gate lines and data lines, or a thin film transistor (TFT) formation part corresponds to a high step 80. This single wiring region corresponds to a portion 85 having a relatively low step.

In the liquid crystal display device of the present invention, the positions of the first column spacer 301 and the second column spacer 302 can be changed depending on the design of the first substrate 100 (TFT substrate). At this time, the first column spacer 301 is formed at the intersection 80 between the gate line and the data line, or at a relatively high step 80 such as a thin film transistor forming portion, thereby forming a single gate line or data. Compared with the second column spacer 302 formed corresponding to the low step portion 85, such as a line, a single metal line and / or semiconductor layer is further included below the second column spacer 302. The thickness that shrinks while pushing is large. At this time, the shrinking thickness acts on the gravity margin.

As a result of the experiment, when the level difference of the relatively high level portion 80 of the first substrate 100 corresponding to the first column spacer 301 is in the range of about 2000 mm to 6000 mm, the gravity defect can be improved as compared with the conventional case. I understand that. At this time, the second column spacer 302 is formed so as to be in contact with the first substrate 100 as shown in FIG. 7A or separated within a predetermined range as shown in FIG. 7B. Alternatively, as shown in FIG. 7C, it is formed to be pushed within a predetermined range.

Here, the degree to which the second column spacer 302 pushes the first substrate 100 apart is limited to about ± 2000 mm. This results in touch unevenness when the second column spacer 302 is 2000 mm or more and further presses the first substrate 100, and when the second column spacer 302 is separated from the first substrate 100 by 2000 mm or more, This is because the cell gap collapses when external pressure is applied, resulting in poor pressing.

In this case, the arrangement degree of the first column spacer 301 and the second column spacer 302 can be changed to a portion where the difference in level difference is relatively small or large depending on the required gravitational defect compensation amount.

That is, if the environment in which the panel is placed is stable, as shown in FIG. 7B, only the first column spacer 301 is formed to push the first substrate 100 with a thickness of about 2000 mm to 4000 mm, and the second column Even if the spacers 302 are formed apart from each other, they are sufficiently resistant to gravity failure. In this case, the distance between the second column spacers 302 is set to 2000 mm or less so as to have sufficient resistance against external pressure.

On the other hand, if the environment in which the panel is placed is inferior, such as a drastic change in high and low temperatures, as shown in FIG. 7C, the first column spacer 301 is formed to have a gravity margin in the range of 4000 mm to 6000 mm, and the liquid crystal It must be formed so as to have a sufficient gravity margin for the expansion force. In this case, the pressing degree of the first substrate of the second column spacer 302 must be within 2000 mm to prevent an increase in frictional force between the second column spacer 302 and the first substrate 100. This is to prevent touch unevenness.

The first column spacer 301 and the second column spacer 302 are formed on the second substrate 200. In order to prevent a decrease in the aperture ratio, the first substrate 100 is provided with a wiring region of a gate line or a data line, Alternatively, the second substrate 200 is formed to correspond to the black matrix layer 201 in correspondence with the thin film transistor forming portion.

Even if the first column spacer 301 and the second column spacer 302 are formed at the same height on the second substrate 200, the first column spacer 301 is a region 80 having a relatively high level difference when bonded. Therefore, the first column spacer 301 contracts by the difference in level difference between the corresponding portions of the first column spacer 301 and the second column spacer 302, and after bonding, the first column spacer 301 has a relatively lower height. It looks as if it was formed.

The case where the second column spacers 302 are simply in contact with each other, separated at a predetermined interval, or pressed at a predetermined interval has been described above. For all of them, the liquid crystal display device of the present invention is , Has the effect of improving the gravity margin.

The degree of correspondence of the second column spacer 302 is also determined by the step of the low step portion 85 generated in the first substrate 100. In addition, the height of each column spacer during patterning for forming the column spacer is determined. It also occurs due to differences.

The present invention corresponds to each case where a difference in height occurs during such patterning, and compensates for non-uniform gravity in the panel caused by the difference in height during patterning of the column spacer.

Hereinafter, specific embodiments of the present invention described above will be described. On the other hand, since the structure and manufacturing process of a TFT substrate having a step change depending on the number of masks used, the following description will be made sequentially in the order of 5 masks and 4 mask processes.

First Embodiment FIG. 8 is a plan view showing a liquid crystal display device that specifically embodies the first embodiment of the present invention in the IPS mode. FIG. 9 is a structural cross-sectional view taken along the line II ′ of FIG. 8 showing the liquid crystal display device according to the first embodiment of the present invention. As shown in FIGS. 8 and 9, the liquid crystal display device according to the first embodiment of the present invention includes a first substrate 100 and a second substrate 200 bonded together with a certain space, and the first substrate. The liquid crystal layer 250 is injected between the substrate 100 and the second substrate 200.

On the first substrate 100, a plurality of gate lines 101 and data lines 102 that intersect vertically and define pixel regions are alternately formed in each pixel region where the gate lines 101 and data lines 102 intersect. The pixel electrode 103 and the common electrode 108, and the thin film transistor formed at the intersection of the gate line 101 and the data line 102 are included. Further, a common line 118 disposed in the pixel so as to be parallel to the gate line 101 and a capacitor electrode 113 extending from the pixel electrode 103 and overlapping the upper portion of the common line 118 are further provided.

Specifically, the common line 118 and the common electrode 108 are integrally formed, are formed simultaneously with the gate line 101, and are formed of a low resistance metal such as Cu, Al, Cr, Mo, or Ti.

The pixel electrodes 103 are alternately formed with the common electrodes 108, but these electrodes can be formed at the same time as the data lines 102, or can be formed in different layers (see the drawing). The case where the layers are formed in different layers is illustrated). At this time, the common electrode 108 and the pixel electrode 103 may be alternately formed in a straight line, or may be formed in a zigzag shape as shown in FIG.

An insulating film is further provided between the common electrode 108 and the pixel electrode 103 in order to separate the two patterns, but silicon nitride or silicon oxide having the same component as the gate insulating film or the protective film. An insulating film made of

The thin film transistor includes a gate electrode 101a, a semiconductor layer 104 covering the upper portion of the gate electrode 101a with a predetermined width, and source / drain electrodes 102a and 102b formed on both sides of the gate electrode 101a. .

The manufacture of the first substrate 100 will be described in detail with reference to a five-mask process as shown in FIG. First, a metal material such as Mo, Al, or Cr is deposited on the entire surface of the first substrate 100 by a sputtering method, and then patterned through a first mask (not shown) to form a plurality of gate lines. 101 and a gate electrode 101 a are formed in a shape protruding from the gate line 101. In the same process, a common line 118 is formed in parallel with the gate line 101, and a common electrode 108 protruding from the common line 118 as a zigzag pattern is formed.

Next, an insulating material such as SiNx is deposited on the entire surface of the first substrate 100 including the gate line 101 to form a gate insulating layer 105. Next, a semiconductor layer 104 is formed on the gate insulating film 105 so as to cover the gate electrode 101a.

Here, the semiconductor layer 104 is formed by depositing an amorphous silicon layer 104a and an n + layer 104b doped with phosphorus (P) at a high concentration on the gate insulating film 105, and then depositing a second mask ( The n + layer 104b and the amorphous silicon layer 104a are simultaneously patterned through a not-shown).

Next, a metal material such as Mo, Al, or Cr is deposited on the entire surface by a sputtering method, and patterned using a third mask (not shown), and a source is formed on both sides of the data line 102 and the gate electrode 101a. An electrode 102a and a drain electrode 102b are formed. Here, the source electrode 102 a is formed to protrude from the data line 102.

In such a metal patterning process, over-etching is performed to the n + layer 104b below the source electrode 102a and the drain electrode 102b so that the n + layer 104b is removed from the top of the gate electrode 101a. . Therefore, the amorphous silicon layer is exposed from the upper part of the gate electrode 101a, and this exposed portion is a region defined as a channel region of a thin film transistor (TFT). Here, the layer composed of the amorphous silicon layer and the n + layer is the semiconductor layer 104.

Next, a protective film 106 made of SiNx is deposited on the entire surface of the gate insulating film 105 including the semiconductor layer 104 on which the source electrode 102a and the drain electrode 102b are formed by a chemical vapor deposition (CVD) method. As a material of such a protective film 106, an inorganic substance such as SiNx is mainly applied. Recently, in order to improve the aperture ratio of the liquid crystal cell, BCB (Benzo Cyclo Butene), SOG (Spin On Glass). Organic materials having a low dielectric constant such as acrylic are used.

Next, a part of the protective film 106 on the drain electrode 102b is selectively etched through a fourth mask (not shown) to form a contact hole exposing a part of the drain electrode 102b.

Next, a transparent electrode material is sputtered and deposited on the protective layer 106 so as to sufficiently fill the contact hole, and then patterned through a fifth mask (not shown) to form the pixel region. The common electrode 108 and the pixel electrode 103 are alternately formed as a zigzag pattern. Here, a capacitor electrode 113 is connected to the pixel electrode 103 on the common line 118.

When the first substrate 100 is formed in this manner, the portion where the thin film transistor is formed and the portion where the gate line 101 and the data line 102 overlap are more than the portion where the gate line 101 or the data line 102 is formed. Has a relatively high step.

On the second substrate 200 facing the first substrate 100, a black matrix layer 201 is formed to block light in portions other than the pixel region (gate line and data line region, thin film transistor region); An R, G, B color filter layer 202 for expressing a hue corresponding to the pixel region is formed, and an overcoat layer 203 is formed on the entire surface of the black matrix layer 201 and the color filter layer 202.

Next, a plurality of column spacers 301 and 302 having the same height are formed on a predetermined portion on the common electrode 203, that is, on a portion corresponding to different steps on the first substrate 100.

In the first embodiment of the present invention, the first column spacer 301 is formed at a position corresponding to the portion of the first substrate 100 where the thin film transistor is formed, and the second column spacer 302 is formed on the data line of the first substrate 100. 102 is formed at a position corresponding to the formed portion. At this time, the first column spacer 301 and the second column spacer 302 are formed at the same height.

The first column spacer 301 formed corresponding to the first substrate 100 having a high step is about 2000 mm relative to the first substrate 100 by the pressure applied at the time of bonding after the step of maintaining the cell gap of the liquid crystal layer 250. It is pushed to a thickness of 6000 mm. The first column spacer 301 is responsible for a cell gap maintaining function unique to the spacer, and has a gravity margin corresponding to the thickness pushed by the first substrate 100.

The second column spacers 302 formed at the same height correspond to the first substrate 100 at a portion having a relatively low level after bonding, and therefore, the second column spacer 302 with respect to the first substrate 100 as compared with the first column spacer 301. The degree of pressing is weak. In FIG. 9, the first substrate 100 is illustrated as being simply in contact with the first substrate 100, but in some cases, the first substrate 100 is separated from the first substrate 100 within a range of 2000 mm (corresponding to FIG. 7B) or pushed by the first substrate 100 ( Equivalent to 7C).

The second column spacer 302 is formed to have a resistance to an external pressure that pushes the panel surface outside in addition to the cell gap maintaining function. The second column spacer 302 corresponds to the first substrate 100 to which the second column spacer 302 corresponds. The upper part is formed so as to secure a certain level difference or more from the part corresponding to the first column spacer 301 so that the first substrate 100 does not have a thickness of 2000 mm or more. In addition to the cell gap maintaining function, when the separately formed second column spacer 302 is pressed against the first substrate 100 with a thickness of 2000 mm or more, the second column spacer 302 and the first substrate 100 This is because the frictional force between them increases, and touch unevenness can occur.

Here, the first column spacer 301 and the second column spacer 302 are pressed so that the first column spacer 301 is further recessed as compared with the second column spacer 302 due to the difference in level of the first substrate 100 to which the first column spacer 301 and the second column spacer 302 correspond. The thickness of is determined.

On the other hand, after the arrays of the first substrate 100 and the second substrate 200 are formed and bonded together, the first column spacer 301 maintains a cell gap, which is a function unique to the spacer. Pressurization reduces the height corresponding to the difference in level between the drain electrode 102b portion and the single formation portion of the data line 102, and the first substrate 100 and the second substrate 200 are moved by that height. It comes to support and has a gravity margin. Also, the second column spacer 302 increases the density of the column spacers and improves the resistance to pressing so that the structure of the second substrate 200 is not denatured due to pressing failure.

The first column spacer 301 and the second column spacer 302 may be formed by selectively removing an organic insulating film and a photosensitive organic resin after forming the organic insulating film and the photosensitive organic resin. The first column spacer 301 and the second column spacer 302 are made of an organic material having a lower hardness than a metal material such as a gate line or a data line corresponding to the first substrate 100. After the two substrates 200 are pasted together, the first column spacer 301 corresponding to the high stepped portion first contacts the first substrate 100 and the portion is pushed like an elastic body, resulting in a change in height. .

Here, the applied pressure at the time of bonding is such that the second column spacer 302 contacts the first substrate 100 within about ± 2000 mm. At this time, the thickness of the first column spacer 301 relatively contracted after bonding acts on the gravity margin. According to the drawing, the first column spacer 301 has a semiconductor layer (104 = 104a + 104b) and a gate insulating film relatively to the second column spacer 302 formed corresponding to the single data line 102. Since 105 is formed corresponding to the further formed portion, the pressing degree of the first column spacer 301 corresponds to the thickness of the semiconductor layer (104 = 104a + 104b) and the gate insulating film 105 (in FIG. The two-column spacer 302 is illustrated so as to be in contact with the structure of the first substrate 100 without being pressed).

As described above, the first substrate 100 on which the TFT array is formed and the surface of the second substrate 200 on which the color filter array including the first column spacer 301 and the second column spacer 302 are formed are respectively formed on the first substrate 100. After the alignment film 107 and the second alignment film 204 are formed, a rubbing process is performed. Here, the rubbing process is a process in which the cloth is rubbed with the surfaces of the first alignment film 107 and the second alignment film 204 at a uniform pressure and speed, thereby increasing the surface height of the first alignment film 107 and the second alignment film 204. The step of determining the initial alignment direction of the liquid crystal so that the molecular chains are aligned in a certain direction.

At this time, the portion of the second alignment film 204 formed on the second column spacer 302 is a portion that comes into contact with the first alignment film 107 facing after bonding, and is relatively in comparison with the second column spacer 302 at the time of contact. The components of the alignment film are pushed by the soft characteristics.

The number of the first column spacers 301 and the second column spacers 302 is set to an appropriate level so that a pressing failure does not occur. At this time, if an excessive number of column spacers are distributed in the panel, it will cause a gravity failure that causes the corners of the panel near the ground to swell at high temperatures, or when the panel surface is touched with a finger, it corresponds to the column spacer. The area touched by the first substrate 100 is increased, and the liquid crystal is not recovered again at the touched portion due to the increase of the frictional force, resulting in touch unevenness that causes light leakage in the black state. Therefore, it is important to distribute the number of column spacers appropriately and efficiently.

The second column spacer 302 is formed in one pixel together with the first column spacer 301, so that the density of the entire column spacers distributed in the panel can be increased and a pressing failure can be prevented. . In addition, after the bonding, the first substrate 100 that is opposed to the first substrate 100 is touched to the extent that it is adjacent to the first substrate 100, or the first substrate 100 is separated or pressed within a range of 2000 mm, the second column spacer 302, By reducing the frictional force with the one substrate 100, the touch unevenness can be alleviated.

Further, the first column spacer 301 and the second column spacer 302 coexist in a single pixel so that the density of the column spacer is maintained at an appropriate level, and the first column spacer 301 is a portion having a relatively high step. After the bonding, the height of the first substrate 100 is changed by the pressed thickness, and the supporting force between the first substrate 100 and the second substrate 200 is increased by that amount to reduce the gravity defect. Can be improved.

In the present invention, the first column spacer 301 and the second column spacer 302 are formed by using the level difference of the surface of the first substrate 100 and corresponding to the part having the level difference. The column spacer 301 is used as an application for maintaining the cell gap and improving poor gravity, and the second column spacer 302 is used as an application for improving defects such as pressing failure and touch unevenness.

Here, the first column spacer 301 formed corresponding to a portion having a relatively high step functions as a cell gap maintenance, and the second column spacer 302 formed corresponding to a portion having a relatively low step. The liquid crystal display device configured with the second column spacer 302 touches the first substrate 100 or is separated within a predetermined range as compared with a liquid crystal display device in which only the first column spacer 301 is distributed alone. Alternatively, it is formed so as to be pushed, so that the generation of frictional force between the two substrates is eased even at the time of touching, and there is no difficulty in restoring the original state.

The highest step of the first substrate 100 can be changed according to the TFT array design. Here, the step is illustrated in the drain electrode 102b portion of the thin film transistor. In addition, a contact region between the drain electrode 102b and the pixel electrode or a portion such as the source electrode 102a of the thin film transistor can be used as the highest point by design.

The back surface of the second substrate 200 may further include an ITO film on the entire surface to prevent static electricity generated in the panel.

Second Embodiment FIG. 10 is a structural cross-sectional view taken along the line II ′ of FIG. 8 showing a liquid crystal display device according to a second embodiment of the present invention. As shown in FIG. 10, in the liquid crystal display device according to the second embodiment of the present invention, the first column spacer 301 is formed at a position corresponding to the portion of the first substrate 100 where the thin film transistor is formed. The second column spacer 302 is formed at a corresponding portion of the gate line 101 formed on the first substrate 100. The remaining structure is the same as the structure of the first embodiment. The functions of the first column spacer 303 and the second column spacer 304 are the same.

Third Embodiment FIG. 11 is a structural cross-sectional view taken along the line II-II ′ of FIG. 8 showing a liquid crystal display device according to a third embodiment of the present invention. As shown in FIG. 11, in the liquid crystal display device according to the third embodiment of the present invention, the first column spacer 305 is formed by using a high step portion of the first substrate 100 as an intersection of the gate line 101 and the data line 102. The second column spacer 306 is formed on the data line 102 having a relatively low step, and is formed at an intersection region of the gate line 101 and the data line 102.

Similar to the first embodiment and the second embodiment, the first column spacer 305 and the second column spacer 306 are formed to correspond to portions having different steps of the first substrate 100, respectively, and have poor pressing and touch. Unevenly, it functions to minimize gravity failure.

Although not shown, in another embodiment, the first column spacer 305 is formed corresponding to the intersection of the gate line 101 and the data line 102 as in the third embodiment, and the second column spacer 306 is formed. Even if the structure is slightly changed so as to correspond only to the gate line 101, the same effect as that of the third embodiment described above can be obtained under the assumption that the height of the gate line 101 and the data 102 is the same.

Fourth Embodiment FIG. 12 is a structural cross-sectional view taken along the line II ′ of FIG. 8 showing a liquid crystal display device according to a fourth embodiment of the present invention. As shown in FIG. 12, a manufacturing method of the liquid crystal display device of the present invention according to the fourth embodiment shown by the 4-mask manufacturing method will be described as follows.

In FIG. 12, first, a metal material such as Mo, Al, or Cr is deposited on the entire surface of the first substrate 100 by a sputtering method, and then patterned through a first mask (not shown). A gate electrode 101 a is formed in a shape protruding from the individual gate lines 101 and the gate lines 101. In the same process, a common line 118 is formed in parallel with the gate line 101, and a common electrode 108 protruding from the common line 118 as a zigzag pattern is formed.

Next, a gate insulating film 105, an amorphous silicon layer 104a, an n + layer 104b, and a source / drain electrode layer (same layer as 102) are sequentially deposited on the entire surface of the first substrate 100 including the gate line 101. .

Next, using a second mask (not shown), first, the source / drain electrode layer, the n + layer 104b, and the amorphous silicon layer 104a are selectively removed, and the data line 102, A pattern protruding from the data line 102 to the drain electrode formation portion is formed. At this time, an n + layer 104b and an amorphous silicon layer 104a having the same width are formed below the patterned source / drain electrode layers.

Then, using the second mask, the source / drain metal layer and the n + layer 104 corresponding to the upper part of the channel of the semiconductor layer are removed with the same width, and the source / drain electrodes 102a separated from each other are removed. , 102b and semiconductor layers 104a and 104b in which channels are defined.

The second mask is a diffractive mask, and the photosensitive film is completely removed from the transmissive part, and the photosensitive film is removed from the semi-transmissive part to a predetermined thickness. At this time, the blocking unit maintains the initial coating thickness of the photosensitive film. Here, the blocking part is defined corresponding to the source / drain electrodes 105a and 105b and the data line forming part, and the semi-transmissive part is formed in a channel part between the source electrode 105a and the drain electrode 105b. Correspondingly defined.

Next, a protective film 106 made of SiNx is deposited on the entire surface of the gate insulating film 105 including the semiconductor layer 104 on which the source electrode 102a and the drain electrode 102b are formed by a chemical vapor deposition (CVD) method. As a material of such a protective film 106, an inorganic substance such as SiNx is mainly applied. Recently, in order to improve the aperture ratio of the liquid crystal cell, BCB (Benzo Cyclo Butene), SOG (Spin On Glass). Organic materials having a low dielectric constant such as acrylic are used.

Next, a part of the protective film 106 on the drain electrode 102b is selectively etched through a third mask (not shown) to form a contact hole exposing a part of the drain electrode 102b.

Next, a transparent electrode material is sputtered and deposited on the protective layer 106 so as to sufficiently fill the contact hole, and then patterned through a fourth mask (not shown) to form the pixel region. Pixel electrodes 103 are formed alternately with the common electrodes 108.

On the second substrate 200 facing the first substrate 100, a black matrix layer 201 is formed to block light in portions other than the pixel region (gate line and data line region, thin film transistor region); An R, G, B color filter layer 202 for expressing a hue corresponding to the pixel region is formed, and an overcoat layer 203 is formed on the entire surface of the black matrix layer 201 and the color filter layer 202.

Next, a plurality of first column spacers 307 and second column spacers 308 having the same height are formed at predetermined portions on the overcoat layer 203, that is, at portions corresponding to different steps on the first substrate 100. Form. Accordingly, the first column spacer 307 is formed on the second substrate 200 corresponding to a contact region between the thin film transistor having a high step on the first substrate 100 and the pixel electrode. The second column spacer 308 is formed on the second substrate 200 corresponding to a gate line wiring region having a low step on the first substrate 100. Here, the first column spacer 307 functions to maintain a cell gap, which is a function unique to the spacer, and the second column spacer 308 functions to compensate for a pressing failure by increasing the density of the column spacers.

At this time, the first column spacer 307 and the second column spacer 308 correspond to a portion where the drain electrode 102b of the thin film transistor and the pixel electrode 103 are in contact with each other. The same height is formed to support the substrate 200. When the first column spacer 307 and the second column spacer 308 are formed at such a height, after the bonding, the first column spacer 307 pushes the first substrate 100, and the first column spacer 307 and the second column spacer 307 are pressed. The height contracts by a thickness corresponding to the difference in level of the first substrate 100 to which the spacer 308 corresponds, and the second column spacer 308 contacts the first substrate 100.

In the drawing, the reason why the first column spacer 307 and the second column spacer 308 are formed corresponding to the thin film transistor formation portion and the gate line region, respectively, is that the black matrix layer 201 that does not damage the aperture ratio is used. It is for shielding.

As described above, the first column spacer 307 and the second column spacer 308 are formed in the above-described column spacer manufacturing process. In addition, the first column spacer 307 and the second column spacer 308 are formed in the portion of the black matrix layer 201 of the second substrate 200 so that the aperture ratio does not drop due to the formation of the column spacer.

The first alignment film 107 and the second alignment film 204 are formed on the surfaces of the first substrate 100 on which the TFT array is formed in this way and the second substrate 200 on which the color filter array is formed, respectively, followed by a rubbing process. do. Here, the rubbing treatment is a process in which the cloth is rubbed with the surfaces of the first alignment film 107 and the second alignment film 204 at a uniform pressure and speed, thereby increasing the height of the surfaces of the first alignment film 107 and the second alignment film 204. The step of determining the initial alignment direction of the liquid crystal so that the molecular chains are aligned in a certain direction.

Fifth Embodiment FIG. 13 is a structural cross-sectional view taken along the line II-II ′ of FIG. 8 showing a liquid crystal display device according to a fifth embodiment of the present invention. As shown in FIG. 13, in the liquid crystal display device according to the fifth embodiment of the present invention, the first column spacer 309 is at the intersection of the gate line 101 and the data line 102, and the second column spacer 310 is at the gate line 308. Except for the point corresponding to the upper part, it is formed by the same method as the fourth embodiment, and has the same effect.

In this case, since the liquid crystal display device according to the fifth embodiment is manufactured with four masks, the patterning of the data line 102 and the patterning of the n + layer 102b and the amorphous silicon layer 104a are performed using the same mask. In addition, the semiconductor layers 104a and 104b are laminated together on the portion of the data line 102 where the metal remains except for the portion corresponding to the channel.

Therefore, the intersection of the gate line 101 and the data line 102 is further formed with the amorphous silicon layer 104a, the n + layer, and the data line 102 as compared with the portion where the single gate line 101 is formed. Compared with the portion of the gate line 101, there is a step that is higher than the thickness of the laminated amorphous silicon layer 104a, n + layer, and data line 102 described above.

Accordingly, when the first column spacer 309 is formed corresponding to the intersection of the gate line 101 and the data line 102 and the second column spacer 310 is formed at the single gate line 101, the first column spacer 309 is: Compared with the second column spacer 310, it is pushed more by the thickness of the laminated amorphous silicon layer 104 a, n + layer, and data line 102.

Sixth Embodiment FIG. 14 is a plan view showing a liquid crystal display device according to the present invention when it is implemented in a TN mode. 15 is a structural cross-sectional view taken along line III-III ′ of FIG. 9 according to the sixth embodiment of the present invention. 14 and 15, the liquid crystal display device according to the sixth embodiment includes a first substrate 100 and a second substrate 200 which are bonded to each other with a certain space, and the first substrate 100 and the second substrate 200. And a liquid crystal layer 250 injected between them.

A plurality of gate lines 101 and data lines 102 that vertically intersect the first substrate 100 to define pixel areas, and pixel electrodes formed in the pixel areas where the gate lines 101 and data lines 102 intersect. 103 and a thin film transistor formed at a portion where the gate line 101 and the data line 102 intersect.

The thin film transistor includes a gate electrode 101a, a semiconductor layer 104 covering the upper portion of the gate electrode 101a with a predetermined width, and source / drain electrodes 102a and 102b formed on both sides of the gate electrode 101a. .

Such a TN mode liquid crystal display device is different from the IPS mode liquid crystal display described above in that pixel electrodes are formed in a single pattern in a pixel region in the first substrate 100, and the second substrate 100 Since the common electrode 205 is formed on the entire surface instead of the overcoat layer (see 203 in FIG. 9), other structures and manufacturing methods have been described in the first to fifth embodiments. It is the same as that.

The method for manufacturing the liquid crystal display device according to the sixth embodiment will be described below.

First, a metal material such as Mo, Al, or Cr is deposited on the entire surface of the first substrate 100 by a sputtering method, and then patterned through a first mask (not shown) to form a plurality of gate lines. 101 and a gate electrode 101 a are formed in a shape protruding from the gate line 101.

Next, an insulating material such as SiNx is deposited on the entire surface of the first substrate 100 including the gate line 101 to form a gate insulating layer 105. Next, a semiconductor layer 104 is formed on the gate insulating film 105 so as to cover the gate electrode 101a. Here, the semiconductor layer 104 is formed by depositing an amorphous silicon layer 104a and an n + layer 104b doped with phosphorus (P) at a high concentration on the gate insulating film 105, and then depositing a second mask ( The n + layer 104b and the amorphous silicon layer 104a are simultaneously patterned through a not-shown).

Next, a metal material such as Mo, Al, or Cr is deposited on the entire surface by a sputtering method, and then patterned using a third mask (not shown) to form both sides of the data line 102 and the gate electrode 101a. A source electrode 102a and a drain electrode 102b are formed. Here, the source electrode 102 a is formed to protrude from the data line 102.

In such a metal patterning process, over-etching is performed to the n + layer 104b below the source electrode 102a and the drain electrode 102b so that the n + layer 104b is removed from the top of the gate electrode 101a. . Therefore, the amorphous silicon layer is exposed from the top of the gate electrode 101a, and the exposed portion is a region defined as a channel region of a thin film transistor (TFT). Here, the semiconductor layer 104 includes the amorphous silicon layer and the n + layer.

Next, a protective film 106 made of SiNx is deposited on the entire surface of the gate insulating film 105 including the semiconductor layer 104 on which the source electrode 102a and the drain electrode 102b are formed by a chemical vapor deposition (CVD) method. As a material of such a protective film 106, an inorganic substance such as SiNx is mainly applied. Recently, in order to improve the aperture ratio of the liquid crystal cell, BCB (Benzo Cyclo Butene), SOG (Spin On Glass). Organic materials having a low dielectric constant such as acrylic are used.

Next, a part of the protective film 106 on the drain electrode 102b is selectively etched through a fourth mask (not shown) to form a contact hole exposing a part of the drain electrode 102b.

Next, a transparent electrode material is sputtered and deposited on the protective film 106 so as to sufficiently fill the contact hole, and then patterned through a fifth mask (not shown) to form the pixel electrode 103 in the pixel region. Form.

As described above, when the first substrate 100 is formed, a portion where the thin film transistor is formed and a portion where the gate line 101 and the data line 102 overlap each other than a portion where the gate line 101 or the data line 102 is formed. Has a relatively high step.

On the second substrate 200 facing the first substrate 100, a black matrix layer (201 in FIG. 9) for blocking light in portions excluding the pixel region (gate line and data line region, thin film transistor region). R), G, and B color filter layers (see 202 in FIG. 9) for expressing the hue corresponding to the pixel region, and the black matrix layer 201 and the color filter layer 202 are formed. A common electrode (according to position 203 in FIG. 9) is formed on the entire upper surface.

Next, a plurality of first column spacers 311 and second column spacers 311 having the same height are formed at predetermined positions on the common electrode 203, that is, at positions corresponding to different steps on the first substrate 100. To do.

In the sixth embodiment of the present invention, the first column spacer 311 is formed at a position corresponding to the portion of the first substrate 100 where the thin film transistor is formed, and the second column spacer 312 is formed on the data line of the first substrate 100. 102 is formed at a position corresponding to the formed portion.

In the above, only the manufacturing method of the liquid crystal display device according to the sixth embodiment in which the first embodiment of the IPS mode is applied to the TN mode has been described, but according to the second to fifth embodiments of the IPS mode in the same manner. The method can also be applied to the TN mode.

As described above, the liquid crystal display device and the manufacturing method thereof according to the present invention are characterized in that column spacers having the same height are formed corresponding to the points of the first substrate (TFT substrate) having different steps. Here, the steps different from each other may be changed depending on the manufacturing method used in the array forming process of the first substrate.

In the embodiment described above, the different steps are different from each other in the first column on the black matrix layer of the second substrate (color filter substrate) corresponding to the highest point and the lowest point of the first substrate. A spacer and a second column spacer were formed. The highest and lowest points of the height can be changed according to the manufacturing method, and the first column spacer is in contact with the first substrate, and the second column spacer is at a predetermined distance from the first substrate. The same effect can be achieved if the distance is satisfied.

It is an expansion perspective view which shows a general liquid crystal display device. It is a flowchart of the manufacturing method of a liquid crystal injection type liquid crystal display device. It is a flowchart of the manufacturing method of a liquid crystal dropping type liquid crystal display device. It is a structural sectional view showing a color filter substrate on which a column spacer is formed. It is structural sectional drawing which shows the shape at the time of bonding of a TFT substrate and a color filter substrate. It is a top view which shows the shape of the site | part which a touch nonuniformity produces. It is sectional drawing which shows the shape of the site | part which a touch nonuniformity produces. It is a graph which shows the touch nonuniformity and gravity defect accompanying the liquid crystal dripping amount and the density change of a column spacer. 1 is a structural cross-sectional view schematically showing a liquid crystal display device of the present invention. 1 is a structural cross-sectional view schematically showing a liquid crystal display device of the present invention. 1 is a structural cross-sectional view schematically showing a liquid crystal display device of the present invention. 1 is a plan view showing a liquid crystal display device that specifically embodies the first embodiment of the present invention in an IPS mode. FIG. 9 is a structural cross-sectional view taken along the line II ′ of FIG. 8 illustrating the liquid crystal display device according to the first embodiment of the present invention. FIG. 9 is a structural cross-sectional view taken along the line II ′ of FIG. 8 showing a liquid crystal display device according to a second embodiment of the present invention. It is a structure sectional view on the II-II 'line of Drawing 8 showing the liquid crystal display concerning a 3rd embodiment of the present invention. It is a structure sectional view on the II 'line of Drawing 8 showing the liquid crystal display concerning a 4th embodiment of the present invention. FIG. 9 is a structural cross-sectional view taken along the line II-II ′ of FIG. 8 illustrating a liquid crystal display device according to a fifth embodiment of the present invention. 1 is a plan view illustrating a liquid crystal display device according to an embodiment of the present invention in a TN mode. It is structural sectional drawing on the III-III 'line of FIG. 9 which concerns on 6th Embodiment of this invention.

Explanation of symbols

100 first substrate, 101 gate line, 101a gate electrode, 102 data line, 102a source electrode, 102b drain electrode, 103 pixel electrode, 104a amorphous silicon layer, 104b n + layer, 105 gate insulating film, 106 protective film, 107 First alignment film, 200 Second substrate, 201 Black matrix layer, 202 Color filter layer, 203 Common electrode, 204 Second alignment film, 250 Liquid crystal layer, 301 to 312 Column spacer.

Claims (43)

A first substrate having a first region having a relatively high step and a second region having a relatively low step; and a first column spacer in a portion corresponding to the first region of the first substrate, A second substrate provided with a second column spacer in a portion corresponding to the two regions and bonded to the first substrate; and a liquid crystal layer formed between the first substrate and the second substrate. A liquid crystal display device characterized by the above. The liquid crystal display device of claim 1, wherein the first column spacer and the second column spacer have the same height. 2. The liquid crystal display device according to claim 1, wherein the first column spacer maintains a cell gap of the liquid crystal layer by pressing a corresponding surface on the first substrate. 4. The liquid crystal display device according to claim 3, wherein the height of the first column spacer contracts by a height difference between the first region and the second region of the first substrate. 5. The liquid crystal display device according to claim 4, wherein the first column spacer contracts to a thickness of 2000 to 6000 mm. The liquid crystal display device of claim 1, wherein the second column spacer is in contact with the first substrate. The liquid crystal display device according to claim 1, wherein the second column spacer is separated from the first substrate at a predetermined interval. The liquid crystal display of claim 1, wherein a first height of the second column spacer is reduced to a second height when pressure is applied to the second substrate. 2. The liquid crystal display device according to claim 1, wherein a TFT array is formed on the first substrate, and a color filter array is formed on the second substrate. The TFT array defines a pixel region on a first substrate, and includes a plurality of gate lines and data lines that intersect perpendicularly to each other, and a plurality of thin film transistors formed at intersections of the gate lines and data lines. The liquid crystal display device according to claim 9, further comprising: a plurality of common electrodes and pixel electrodes alternately formed in each pixel region. The color filter array comprises: a black matrix layer formed on a second substrate corresponding to the metal wiring and thin film transistor of the TFT array; a color filter layer formed on the second substrate including the black matrix layer; The liquid crystal display device according to claim 9, further comprising an overcoat layer formed on the color filter layer. The liquid crystal display of claim 11, wherein the first column spacer is formed corresponding to a source electrode of the thin film transistor. 12. The liquid crystal display device according to claim 11, wherein the first column spacer is formed corresponding to a drain electrode of the thin film transistor. The liquid crystal display device of claim 11, wherein the first column spacer is formed corresponding to an upper portion of the gate electrode of the thin film transistor. The liquid crystal display device of claim 11, wherein the first column spacer is formed corresponding to a contact region between the thin film transistor and the pixel electrode. 12. The liquid crystal display device according to claim 11, further comprising an ITO film on the entire back surface of the first substrate. 12. The liquid crystal display device according to claim 11, wherein the plurality of column spacers are formed on the color filter array. The liquid crystal display device of claim 11, wherein the first column spacer and the second column spacer are formed on the black matrix layer. The TFT array defines a pixel region, and a plurality of gate lines and data lines that intersect perpendicularly to each other, a plurality of thin film transistors formed at intersections of the gate lines and the data lines, The liquid crystal display device according to claim 9, comprising a plurality of pixel electrodes formed in each pixel region. The color filter array includes a black matrix layer formed corresponding to a metal wiring and a thin film transistor forming part of the TFT array, a color filter layer formed on a second substrate including the black matrix layer, and the color The liquid crystal display device according to claim 19, comprising a common electrode formed on the filter layer. The liquid crystal display of claim 20, wherein the first column spacer is formed corresponding to a source electrode of the thin film transistor. The liquid crystal display of claim 20, wherein the first column spacer is formed corresponding to a drain electrode of the thin film transistor. The liquid crystal display of claim 20, wherein the first column spacer is formed corresponding to an upper part of the gate electrode of the thin film transistor. 21. The liquid crystal display device of claim 20, wherein the first column spacer is formed corresponding to a region where the one thin film transistor and the one pixel electrode are in contact with each other. 21. The liquid crystal display device of claim 20, wherein the first column spacer and the second column spacer are formed corresponding to the black matrix layer forming portion. The liquid crystal display device according to claim 1, further comprising a plurality of alignment films formed on surfaces of the first substrate and the second substrate facing each other. A first substrate and a second substrate facing each other; a plurality of gate lines and data lines formed on the first substrate to define a pixel region; and the gate lines and the data. A plurality of thin film transistors formed at intersections of the lines; a plurality of pixel electrodes and a common electrode formed in each pixel region; and formed on the second substrate corresponding to the one thin film transistor. A first column spacer, a second column spacer formed on the second substrate corresponding to the one gate line or the one data line, and between the first substrate and the second substrate. A liquid crystal display device comprising: a formed liquid crystal layer. The first thickness of the first column spacer is reduced to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate. 27. A liquid crystal display device according to 27. 28. The liquid crystal display device of claim 27, wherein the first column spacer and the second column spacer are formed at the same height. A first substrate and a second substrate facing each other; a plurality of gate lines and data lines formed on the first substrate to define a pixel region; and the gate lines and the data. A plurality of thin film transistors formed at intersections of the lines, a plurality of pixel electrodes formed in each pixel region, and a second thin film transistor formed on the second substrate corresponding to the one thin film transistor. A column spacer; a second column spacer formed on the second substrate corresponding to the one gate line or the one data line; and formed between the first substrate and the second substrate. A liquid crystal display device comprising: a liquid crystal layer. The first thickness of the first column spacer is reduced to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate. 30. A liquid crystal display device according to 30. The liquid crystal display of claim 30, wherein the first column spacer and the second column spacer are formed at the same height. A first substrate and a second substrate facing each other; a plurality of gate lines and data lines formed on the first substrate to define a pixel region; and the gate lines and the data. A plurality of thin film transistors formed at intersections of lines; a plurality of pixel electrodes and common electrodes formed at each pixel region; and the second corresponding to the intersection of the gate lines and the data lines. A first column spacer formed on the substrate; a second column spacer formed on the second substrate corresponding to a gate line or a data line excluding an intersection of the gate line and the data line; A liquid crystal display device comprising: a liquid crystal layer formed between the first substrate and the second substrate. The first thickness of the first column spacer is reduced to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate. 34. A liquid crystal display device according to 33. The liquid crystal display of claim 33, wherein the first column spacer and the second column spacer are formed at the same height. A first substrate and a second substrate facing each other; a plurality of gate lines and data lines formed on the first substrate to define a pixel region; and the gate lines and the data. A plurality of thin film transistors formed at intersections of the lines, a plurality of pixel electrodes formed in the pixel regions, and on the second substrate corresponding to the intersections of the gate lines and the data lines. A first column spacer formed; a second column spacer formed on the second substrate corresponding to a gate line or a data line excluding an intersection of the gate line and the data line; and the first substrate. And a liquid crystal layer formed between the second substrate and the liquid crystal display device. The first thickness of the first column spacer is reduced to a second thickness when pressure is applied to the first substrate, and the second column spacer contacts the first substrate. 36. A liquid crystal display device according to 36. The liquid crystal display device of claim 36, wherein the first column spacer and the second column spacer are formed at the same height. Providing a first substrate on which a TFT array is formed;
Preparing a second substrate having a color filter array formed so as to face the first substrate; a first region having a relatively high step; and a second region having a relatively low step. Forming a first column spacer and a second column spacer on a second substrate; forming a liquid crystal layer between the first substrate and the second substrate; and the first substrate and the second substrate A method for manufacturing a liquid crystal display device comprising the steps of: The first column spacer is formed on a second substrate corresponding to a first region of the thin film transistor array of the first substrate, and the second column spacer is a gate line excluding the first region of the first substrate. 40. The method of manufacturing a liquid crystal display device according to claim 39, wherein the liquid crystal display device is formed corresponding to a data line area. 40. The method of claim 39, wherein the first region of the first substrate corresponds to a thin film transistor region of the thin film transistor array. The method according to claim 39, wherein the first region of the thin film transistor array formed on the first substrate corresponds to an intersection of the gate line and the data line. The method according to claim 39, wherein the first column spacer and the second column spacer are formed at the same height.

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